ABSTRACT
Description of Anodic Dissolution ....................................................... 152 3.1.4 Electrochemical Techniques in the Study of Anodic Dissolution .................. 154
3.1.4.1 ClassiŽcation of Electrochemical Techniques ..................................... 154 3.1.4.2 Nonsteady-State versus Steady-State Techniques .............................. 155 3.1.4.3 Background of Time-/Frequency-Resolved Measurements
with an Upstream (Emitter)–Downstream (Collector) Electrode Setup ....................................................................................... 159
3.1.4.4 Anodic Dissolution of Metals and Inductive Behaviors ................... 161 3.2 Anodic Dissolution of Pure Metals ................................................................................. 165
3.2.1 Mechanism of Heterogeneous Reaction: Dissolution in the Active State ..... 165 3.2.1.1 Active Dissolution of Iron in Acidic Solutions ................................... 165 3.2.1.2 Role of Anions in the Anodic Dissolution of Iron .............................. 173 3.2.1.3 Active Dissolution of Other Metals ...................................................... 174 3.2.1.4 Recent Advances in the Mechanism of Passivation
by Downstream Collector Electrode Techniques ............................... 175 3.2.2 Dissolution in the Passive State ........................................................................... 178
3.2.2.1 Film Relaxation and Dissolution in the Passive State ........................ 178 3.2.3 Anodic Dissolution under Mass Transport Control ......................................... 188
3.2.3.1 Mass Transport Control and Corrosion ............................................... 188 3.2.3.2 Active Dissolution of Iron under Mass Transport Control ............... 189 3.2.3.3 Anodic Dissolution Controlled by Transport in the Presence
of Solid Layers ......................................................................................... 190 3.3 Anodic Behavior of Alloys ............................................................................................... 192
3.3.1 The Basic Concepts: A Survey .............................................................................. 192 3.3.1.1 Thermodynamics and Rate Constant Approaches ............................ 192 3.3.1.2 Simultaneous Dissolution and Associated Formalism ..................... 193 3.3.1.3 Selective Dissolution ............................................................................... 194
The anodic dissolution of a metal is an electrochemical oxidation of its surface atoms resulting Žnally in the liberation of cations into the electrolyte. Anodic dissolution is of basic importance not only in corrosion but also in several technologies: negative electrodes of primary and secondary batteries, electromachining, electropolishing, and electrowinning of metals, anodes for electrodeposition and cathodic protection, and so forth.
